Writing a column for Six Colors this week (appears Monday) in answer to a reader question, I realized the utility I wanted to recommend that they use didn’t exist. So I wrote it. Please welcome a new, free Mac app called Mister Plimsoll. It has a single-minded purpose: you set a threshold as a percentage of storage full for any volume you want to monitor. If that threshold is exceeded, Mister Plimsoll can pop-up a Mac alert, send you an email, and post an iMessage. You can choose one, two, or three of those options.

The app is in beta. It will remain free after beta, too! I’m actively looking for feedback on improving while keeping mission creep at a minimum. (I have too many utility apps with one purpose in mind that also let you map any keystroke in the system, provide weather updates, etc.) There’s a tip link for those who find it useful.

Why Mister Plimsoll? I considered Mister Creosote, a reference to a famous Monty Python bit in The Meaning of Life, but they came up with that name and have some claim on it under copyright law (not trademark law), and it is a little gross. To avoid conflict, I decided to reference Samuel Plimsoll, the sailors’ friend, who developed a simple marking system to avoid overloading ships with freight, thus making them likely to sink. In his honor, this app will keep your volume from becoming so laden, it founders.